Q:how to increment file creation from an event?

Question

I tried to create a txt file for every new message from Telegram using telethon event. I would like to have txt file like OIF ,OIF1, OIF2,OIF3 ... for every message I get

Thanks for help
That's my code

client.start()
@client.on(events.NewMessage(chats='tradingnava'))
async def my_event_handler(event):
    texte = (event.text)
    texte = texte.split(" ")
    Marche = texte[1]
    Direction = texte[2]
    i = 0
    while os.path.exists('OIF%s.txt' % i):
        i += 1
        if Direction == 'buy':
            f= open(r'C:\Users\USER\PycharmProjects\rakna2\OIF%s.txt' %i, "w")
            f.write("buy b a")
            f.close()
        if Direction == 'sell':
            f= open(r'C:\Users\USER\PycharmProjects\rakna2\OIF%s.txt" %i, "w")
            f.write("sell b a")
            f.close()

Answer 1

import os
import re

path = r'C:\\Users\\USER\\PycharmProjects\\rakna2\\'
client.start()
@client.on(events.NewMessage(chats='tradingnava'))
async def my_event_handler(event):
    texte = (event.text)
    texte = texte.split(" ")
    Marche = texte[1]
    Direction = texte[2]

    allfile = [int(re.findall(f'\d+', fname)[0]) for fname in os.listdir(path) 
               if fname.startswith("OIF") and re.findall(f'\d+', fname)]
    try:
        s = str(max(allfile) + 1)
    except ValueError:
        allfile = [0]
    
    with open(r'OIF%s.txt' %str(max(allfile) + 1), 'w') as f:
        Direction = 'buy'
        if Direction == 'buy':
            f.write("buy b a")
            f.close()
        elif Direction == 'sell':
            f.write("sell b a")
            f.close()
        else:
            f.write(f"Direction Error {Direction}")
            f.close()